<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8" />
		<title>4.数组</title>
	</head>
	<body>
		<script type="text/javascript" >
			let arr = [1,2,3]
			arr.push(4)
			console.log(arr)
			console.log(arr.push === Array.prototype.push)
		</script>
	</body>
</html>